Merge branch 'sctp'

Wang Weidong says:

====================
sctp: check the rto_min and rto_max

v6 -> v7:
  -patch2: fix the whitespace issues which pointed out by Daniel

v5 -> v6:
  split the v5' first patch to patch1 and patch2, and remove the
  macro in constants.h

  -patch1: do rto_min/max socket option handling in its own patch, and
   fix the check of rto_min/max.
  -patch2: do rto_min/max sysctl handling in its own patch.
  -patch3: add Suggested-by Daniel.

v4 -> v5:
  - patch1: add marco in constants.h and fix up spacing as
    suggested by Daniel
  - patch2: add a patch for fix up do_hmac_alg for according
    to do_rto_min[max]

v3 -> v4:
  -patch1: fix use init_net directly which suggested by Vlad.

v2 -> v3:
  -patch1: add proc_handler for check rto_min and rto_max which suggested
   by Vlad

v1 -> v2:
  -patch1: fix the From Name which pointed out by David, and
   add the ACK by Neil
====================

Signed-off-by: David S. Miller <davem@davemloft.net>